In his committee appearance, Dr Fox also accused the EU of acting like a "gang" over Brexit negotiations, suggesting an exit agreement that moved away from the current UK-EU relationship would be a "political" choice.

He said: "The language, which is regrettable, that some people want to punish Britain for leaving in case any other people would want to leave is the language of a gang and not the language of a club.

"In the longer-term it's in the interests of all EU citizens to maintain an open, liberal trading environment."

Commenting on Dr Fox's committee appearance, Labour MP Chris Leslie - a supporter of the pro-EU Open Britain campaign - accused the Brexit supporter of being "disgracefully complacent about the prospect of a deal with the US leading to a flood of chlorinated chicken invading our supermarkets".